Microsoft has cut a deal to open Windows stores within 500 Best Buy locations in the United States and 100 more Best Buy and Future Shop locations in Canada.

The store-within-a-store sites, which will be 1,500 square feet to 2,200 square feet, will offer a wide selection of Windows tablets and PCs, Windows Phones, Microsoft Office, and Xbox consoles. There will also be space set aside specifically for Microsoft's Surface tablet computers.

The deal, announced Thursday, also calls for more than 1,200 Best Buy sales staff to receive Microsoft training, in addition to the Microsoft specialists already on staff at Best Buy.

Capossela noted that the Windows store-within-stores will run, on average, ten times larger than the Apple shops in Best Buy, and five times larger than the Samsung ones. And while the Windows stores will also feature the company's phones, tablets, and gaming console, Best Buy will continue to carry those products in the device-specific departments of its stores as well.

Best Buy opened three trial locations of its Windows stores Thursday, in Rochester, Minn., Ft. Worth, Texas, and Louisville, Texas, to see what works and what needs refinement. It plans the broader rollout later this month, which will continue throughout the summer so they are set up in time for back-to-school shopping. Capossela declined to say how long the contract with Best Buy would last, except to note that it was a "multiyear" agreement.

Since the launch of Windows 8 last fall, Microsoft has been criticized, even by some partners, for confusing customers by offering two types of tablets - one running Windows 8, the other with Windows RT. Capossela said that just as Microsoft engineers "reimagined" Windows, adding touch capabilities throughout the computing experience, the company also needs to rethink its approach to retail sales of the new operating system.

"We also have to innovate on the shopping experience," Capossela said. "We have to make it easy to understand."

Best Buy is also rolling out an online version of the Windows store-within-a-store, creating a Web site where consumers can find information about promotions.

The companies didn't disclose terms of the partnership, though Capossela called it "a major investment for both sides."

Update, 9:40 a.m. and 10:30 a.m. PT:Adds more details from the announcement and comment from Microsoft.